Improve codegen for intrinsics #7851
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… semantics. Also added unit tests of range code to test refactoring. The num-range-rev.rs test will need to be updated when the range_rev semantics change.
… only, not type signatures)
…fclosedness-issue5270-2ndpr, r=cmr Changes int/uint range_rev to iterate over range `(hi,lo]` instead of `[hi,lo)`. Fix rust-lang#5270. Also: * Adds unit tests for int/uint range functions * Updates the uses of `range_rev` to account for the new semantics. (Note that pretty much all of the updates there were strict improvements to the code in question; yay!) * Exposes new function, `range_step_inclusive`, which does the range `[hi,lo]`, (at least when `hi-lo` is a multiple of the `step` parameter). * Special-cases when `|step| == 1` removing unnecessary bounds-check. (I did not check whether LLVM was already performing this optimization; I figure it would be a net win to not leave that analysis to the compiler. If reviewer objects, I can easily remove that from the refactored code.) (This pull request is a rebased version of PR rust-lang#7524, which went stale due to recent unrelated changes to num libraries.)
Allowing them in type signatures is a significant amount of extra work, unfortunately. This also doesn't apply to static values, which takes a different code path.
Simulates borrow checks for '@mut' boxes, or at least it's the same idea.
…e-unwrap, r=pcwalton Fixes Issue rust-lang#7764 Running `make check` I do get a failure: test rt::io::extensions::test::push_bytes ... ok rustest rt::comm::test::oneshot_single_thread_send_port_close ... t: task failed at 'Unhandled condition: read_error: {kind: OtherIoError, desc: "Placeholder error. You shouldn\'t be seeing this", detail: None}', /Users/shout/Projects/rust/src/libstd/condition.rs:50 /bin/sh: line 1: 35056 Abort trap: 6 x86_64-apple-darwin/stage2/test/stdtest-x86_64-apple-darwin --logfile tmp/check-stage2-T-x86_64-apple-darwin-H-x86_64-apple-darwin-std.log make: *** [tmp/check-stage2-T-x86_64-apple-darwin-H-x86_64-apple-darwin-std.ok] Error 134
Whenever a lang_item is required, some relevant message is displayed, often with
a span of what triggered the usage of the lang item.
Now "hello word" is as small as:
```rust
#[no_std];
extern {
fn puts(s: *u8);
}
extern "rust-intrinsic" {
fn transmute<T, U>(t: T) -> U;
}
#[start]
fn main(_: int, _: **u8, _: *u8) -> int {
unsafe {
let (ptr, _): (*u8, uint) = transmute("Hello!");
puts(ptr);
}
return 0;
}
```
…lton Add some codegen tests. Nothing too surprising.
Simulates borrow checks for '@mut' boxes, or at least it's the same idea. This allows you to store owned values, but mutate them while they're owned by TLS. This should remove the necessity for a `pop`/`set` pattern to mutate data structures in TLS.
…felix Adding options for `po4a` in `mk/docs.mk` and updating .pots.
Most arms of the huge match contain the same code, differing only in small details like the name of the llvm intrinsic that is to be called. Thus the duplicated code can be factored out into a few functions that take some parameters to handle the differences.
Currently, our intrinsics are generated as functions that have the usual setup, which means an alloca, and therefore also a jump, for those intrinsics that return an immediate value. This is especially bad for unoptimized builds because it means that an intrinsic like "contains_managed" that should be just "ret 0" or "ret 1" actually ends up allocating stack space, doing a jump and a store/load sequence before it finally returns the value. To fix that, we need a way to stop the generic function declaration mechanism from allocating stack space for the return value. This implicitly also kills the jump, because the block for static allocas isn't required anymore. Additionally, trans_intrinsic needs to build the return itself instead of calling finish_fn, because the latter relies on the availability of the return value pointer. With these changes, we get the bare minimum code required for our intrinsics, which makes them small enough that inlining them makes the resulting code smaller, so we can mark them as "always inline" to get better performing unoptimized builds. Optimized builds also benefit slightly from this change as there's less code for LLVM to translate and the smaller intrinsics help it to make better inlining decisions for a few code paths. Building stage2 librustc gets ~1% faster for the optimized version and 5% for the unoptimized version.
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Fix manual_assert and match_wild_err_arm for `#![no_std]` and Rust 2021 Rust 2015 `std::panic!` has a wrapping block while `core::panic!` and Rust 2021 `std::panic!` does not. See rust-lang#88919 for details. Note that the test won't pass until clippy changes in rust-lang#88860 is synced. --- changelog: Fix [`manual_assert`] and [`match_wild_err_arm`] for `#![no_std]` and Rust 2021. Fixes rust-lang#7723
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